U.S. patent number 6,295,690 [Application Number 09/284,884] was granted by the patent office on 2001-10-02 for wiper blade for cleaning automobile windscreens.
This patent grant is currently assigned to Robert Bosch GmbH. Invention is credited to Thomas Kotlarski, Wilfried Merkel.
United States Patent |
6,295,690 |
Merkel , et al. |
October 2, 2001 |
Wiper blade for cleaning automobile windscreens
Abstract
A wiper blade (10) is proposed that serves to clean windows of
motor vehicles. The wiper blade has an elongated, rubber-elastic
wiper strip (14) which is provided on its two long sides with
respective facing longitudinal grooves (38, 40), in each of which
one spring rail (30, 32), protruding intermittently from the
grooves by one longitudinal edge (42, 44), is disposed; the spring
rails belong to an elongated, spring-elastic support element (12)
for the wiper strip (14), on whose middle portion a connection
device (16) for a wiper arm (18) guided on the vehicle body is
disposed. An especially simple disposition of a wind deflector
strip and a connection device for a wiper arm are obtained if at
least one longitudinal portion of the part of the wiper strip
located on the side of the spring rails (30, 32) remote from the
window is embodied as a wind deflector strip (54), and if
furthermore the connection device (16) is retained on the
longitudinal edges (42, 44) of the spring rails (30, 32) that
protrude from the longitudinal grooves (38, 40).
Inventors: |
Merkel; Wilfried (Kappelrodeck,
DE), Kotlarski; Thomas (Buehlertal, DE) |
Assignee: |
Robert Bosch GmbH (Stuttgart,
DE)
|
Family
ID: |
7841566 |
Appl.
No.: |
09/284,884 |
Filed: |
April 22, 1999 |
PCT
Filed: |
July 23, 1998 |
PCT No.: |
PCT/DE98/02074 |
371
Date: |
April 22, 1999 |
102(e)
Date: |
April 22, 1999 |
PCT
Pub. No.: |
WO99/12784 |
PCT
Pub. Date: |
March 18, 1999 |
Foreign Application Priority Data
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Sep 8, 1997 [DE] |
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197 39 256 |
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Current U.S.
Class: |
15/250.201;
15/250.32; 15/250.43 |
Current CPC
Class: |
B60S
1/3867 (20130101); B60S 1/4006 (20130101); B60S
1/3875 (20130101); B60S 1/3808 (20130101); B60S
1/3806 (20130101); B60S 2001/382 (20130101); B60S
1/3851 (20130101); B60S 1/3874 (20130101); B60S
1/3879 (20130101) |
Current International
Class: |
B60S
1/38 (20060101); B60S 001/38 (); B60S 001/40 () |
Field of
Search: |
;15/250.48,250.201,250.451,250.43,250.452,250.44,250.453,250.32,250.361 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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1028896 |
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Apr 1958 |
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DE |
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1247161 |
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Aug 1967 |
|
DE |
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1505379 |
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Jul 1969 |
|
DE |
|
2458199 |
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Jun 1975 |
|
DE |
|
2839587 |
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Mar 1980 |
|
DE |
|
692226 |
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Jul 1965 |
|
IT |
|
Primary Examiner: Graham; Gary K.
Attorney, Agent or Firm: Striker; Michael J.
Claims
What is claimed is:
1. A wiper blade for cleaning windows of motor vehicles, said wiper
blade comprising
an elongated, rubber-elastic wiper strip (14) provided with
respective longitudinal grooves (38,40) on corresponding opposite
long sides thereof and with a wiper lip (28) for contact with a
window (26);
an elongated spring-elastic support element (12) for the wiper
strip (14), said support element (12) having corresponding spring
rails (30,32) engaged in and protruding from the longitudinal
grooves (38,40) provided in the wiper strip (14);
a connection device (16) for a wiper arm (18) connected to a middle
portion of the support element (12), wherein said spring rails
(30,32) have longitudinal edges (42,44) arranged outside of the
longitudinal grooves (38,40) and said connection device (16) is
held on the longitudinal edges (42,44) of the spring rails (30,32);
and
a wind deflector strip (54) comprising at least one longitudinal
portion of the wiper strip, said at least one longitudinal portion
being located on a side of the spring rails (30,32) remote from the
wiper lip (28); and
retaining means (34,36) for said spring rails (30,32), wherein said
wind deflector strip (54) is provided with at least one recess (62)
for receiving said retaining means, said at least one recess (62)
extending longitudinally along said wind deflector strip (54)
nearly to the longitudinal grooves (38,40), and said retaining
means (34,36) extend across said wind deflector strip (54).
2. The wiper blade as defined in claim 1, wherein said retaining
means (34,36) for said spring rails (30,32) are distributed
longitudinally along said spring rails (30,32).
3. The wiper blade as defined in claim 2, wherein the retaining
means (34,36) comprise respective clamps (72) having claws (74) on
corresponding ends thereof, said claws (74) reach around said
spring rails (32,30) and said claws (74) engage around said
longitudinal edges (42,44) of said spring rails.
4. A wiper blade for cleaning windows of motor vehicles, said wiper
blade comprising
an elongated, rubber-elastic wiper strip (14) provided with
respective longitudinal grooves (38,40) on corresponding opposite
long sides thereof and with a wiper lip (28) for contact with a
window (26);
an elongated spring-elastic support element (12) for the wiper
strip (14), said support element (12) having corresponding spring
rails (30,32) engaged in and protruding from the longitudinal
grooves (38,40) provided in the wiper strip (14);
a connection device (16) for a wiper arm (18) connected to a middle
portion of the support element (12), wherein said spring rails
(30,32) have longitudinal edges (42,44) arranged outside of the
longitudinal grooves (38,40) and said connection device (16) is
held on the longitudinal edges (42,44) of the spring rails (30,32);
and
a wind deflector strip (54) comprising at least one longitudinal
portion of the wiper strip, said at least one longitudinal portion
being located on a side of the spring rails (30,32) remote from the
wiper lip (28);
wherein said wind deflector strip (54) has a substantially
triangular transverse cross-section and a first side (56) facing
predominantly in a wind direction (55), said first side (56)
including a concave surface for wind deflection.
5. The wiper blade as defined in claim 4, wherein said wind
deflector strip (54) has a second side (58) on a side of said wind
deflector strip (54) opposite from said first side (56) and a third
side (60) forming respective walls of said longitudinal grooves
(38,40) for the spring rails.
6. The wiper blade as defined in claim 1 or 4 wherein said wiper
strip (14) has a constant transverse cross-section over an entire
length thereof.
7. The wiper blade as defined in claim 1 or 4, wherein said
connection element (16) is a retaining element for said spring
rails (30,32).
8. The wiper blade as defined in claim 4, further comprising a
plurality of retaining means (34,36) for said spring rails (30,32)
distributed longitudinally along said spring rails (30,32).
9. The wiper blade as defined in claim 8, wherein the retaining
means (34,36) comprise respective clamps (72) having claws (74) on
corresponding ends thereof, said claws (74) reach around said
spring rails (32,30) and said claws (74) engage around longitudinal
edges (42,44) of said spring rails engaged inside of said
longitudinal grooves (38,40) and facing away from each other.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a wiper blade for cleaning windows
of motor vehicles and, more particularly, to a wiper blade
comprising an elongated, rubber-elastic wiper strip provided with
respective longitudinal grooves on its corresponding long sides, a
support element for the wiper strip with corresponding spring rails
engaged in and protruding from the longitudinal grooves and a
connecting device for a wiper arm connected to a middle portion of
the support element.
2. Prior Art
In wiper blades of the prior art the support element is meant to
assure the evenest possible distribution of the wiper blade contact
pressure on the windows, over the entire swept field swept by the
wiper blade. By means of a suitable curvature of the unstressed
support element--that is, when the wiper blade is not applied to
the windshield--the ends of the wiper strip, which in wiper blade
operation are pressed entirely against the window, are urged toward
the window by the then-stressed support element, even if the radii
of curvature of spherically curved vehicle windows differ in every
position of the wiper blade. The curvature of the wiper blade must
accordingly be somewhat greater than the greatest curvature of the
swept field of the window to be wiped. The support element thus
replaces the complicated support bracket construction, having two
spring rails disposed in the wiper strip, of the kind employed in
conventional wiper blades (German Patent Disclosure DE-OS 15 05
379).
In a known wiper blade of this type (German Patent DE-PS 10 28
896), with an attendant buildup of overpressure, the wiper blade
can be engaged from below, on the front side facing into the wind,
by this overpressure. On the other hand, on the back side facing
away from the wind, a considerable negative pressure builds up.
Although the wiper blade, which during operation usually executes a
pendulum motion, constantly changes its position relative to the
oncoming relative wind, even then one of its long sides is always
more or less greatly exposed to the wind and is therefore called
the front side, while its other long side is accordingly also
thought of as the back side. At relatively high vehicle speeds,
given the cooperation of these two aforementioned pressures, both
of which are oriented counter to the wiper blade contact pressure,
this contact pressure is reduced at least enough that proper wiping
is no longer possible. Increasing the wiper blade contact pressure
against the window at high vehicle speeds could admittedly reduce
the severity of this problem, but at lower vehicle speeds, when the
liftoff tendency is less, the friction between the wiper blade and
the window increases; this leads to undesirable noise buildup and
to excessively high stress on the drive components and on the
rubber of the wiper. To suppress the aforementioned tendencies of
the wiper blade to lift off from the window, the accessories trade
offers so-called spoilers, which can be disposed on the wiper blade
and support bracket system. With the wiper blade in question,
however, this cannot be done, because fastening what is as a rule a
rigid spoiler to the support element would render the flexibility
of the support element virtually nil, making proper cleaning of the
prescribed swept field no longer possible.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide an improved
wiper blade which does hot have the above-described
disadvantages.
According to the invention this object and others, which will be
made more apparent hereinafter, are attained in a wiper blade
comprising an elongated, rubber-elastic wiper strip provided with
respective longitudinal grooves on corresponding opposite long
sides thereof and with a wiper lip for contact with a window; a
support element for the wiper strip having respective spring rails
engaged in and protruding from the longitudinal grooves provided in
the wiper strip; a connection device for a wiper arm connected to a
middle portion of the support element, the connection device is
being held on the longitudinal edges of the spring rails arranged
outside of the longitudinal grooves and a wind deflector strip
comprising at least one longitudinal portion of the wiper strip
located on a side of the spring rails remote from the wiper
lip.
In the wiper blade via the leading-edge face of the wind deflector
strip that faces into the wind, a force component aimed at the
window is built up, which counteracts the liftoff tendency of the
two pressures and thus assures excellent cleaning quality, at least
in the region of the swept field swept by the wiper blade, that is,
the region that is important to the vehicle's driver. Depending on
the size of the leading-edge face, this "auxiliary contact
pressure" can be adapted to the variable demands that depend for
instance on the type of vehicle. It is also advantageous in the
arrangement of the invention that as a function of the vehicle
speed, the contact pressure rises or falls with this speed. Thus a
suitably high "auxiliary contact pressure" is opposed only to the
liftoff tendency that occurs at high speed. At the same time, the
longitudinal edges of the spring rails that protrude from the
longitudinal grooves of the wiper strip offer an excellent
capability of positioning and fastening the connection device.
If along its length the wind deflector strip has at least one
recess, extending nearly to the longitudinal grooves, which serves
to receive retaining means, disposed crosswise to the length, for
the two spring rails, then the retaining means can become operative
near their retention/attachment points, thus making undesirable
leverage effects avoidable.
The part of the wiper strip embodied as a wind deflector strip
expediently has a substantially triangular cross section, whose
side facing into the wind is scooped out in concave fashion; the
second side of the wind deflector strip is oriented essentially
perpendicular to the window, and the third side, to form a wind
deflector strip of compact design, forms the one groove wall,
facing away from the window, for the spring rails.
Advantages from a manufacturing standpoint can be obtained if the
wiper strip has a constant cross section substantially over its
entire length.
To stabilize the wiper blade, the spring rails that belong to the
support element can be engaged by a plurality of retaining means
distributed over the length of the spring rails.
In this respect, further advantages from the standpoint of mounting
and assembly are obtained if the connection device is embodied as
retaining means.
An especially simple form of the further retaining means is
obtained if these retaining means are embodied as clamps, which
with claws on their ends reach around the spring rails on the
longitudinal edges facing away from one another.
On the two ends of the wiper blade, mounting the retaining means
becomes easy if the spring rails have their end portions exposed,
and also if clamplike retaining means engage these end
portions.
Further advantageous refinements and features of the invention are
recited in the ensuing description of an exemplary embodiment shown
in the accompanying drawing.
BRIEF DESCRIPTION OF THE DRAWING
The objects, features and advantages of the invention will now be
illustrated in more detail with the aid of the following
description of the preferred embodiments, with reference to the
accompanying figures in which:
FIG. 1 shows a side view of a wiper blade of the invention;
FIG. 2 shows a plan view, not to scale, on a support element
belonging to the wiper blade and in which support element a wind
deflector strip of the wiper blade is shown by dot-dash lines;
FIG. 3 shows a section through the wiper blade, taken along the
line III--III in FIG. 1, on a larger scale;
FIG. 4 shows an enlarged wiping area of the wiper blade along the
line IV--IV in FIG. 1, with the connection device for the wiper arm
shown in dot-dash lines; and
FIG. 5 shows an enlarged view of the support element in the
direction of the arrow V, rotated by 90.degree..
DESCRIPTION OF THE EXEMPLARY EMBODIMENT
A wiper blade 10 shown in FIG. 1 has a multi-part, elongated,
spring-elastic support element 12 (FIG. 2), to whose underside an
elongated, rubber-elastic wiper strip 14' is secured longitudinally
axially parallel to it. A connection device 16 is disposed on the
top side of the support element, and with its aid the wiper blade
10 can be detachably connected to a driven wiper arm 18. A hook
acting as a counterpart connection means is formed onto the free
end 20 of the wiper arm 18 and grasps a pivot pin 22 that belongs
to the connection device 16 of the wiper blade. The connection of
the wiper arm 18 to the wiper blade 10 is performed by securing
means not shown in further detail but known per se and embodied as
adapters. The wiper arm 18 and thus also the hook on the end 20 of
the arm is urged in the direction of the arrow 24 toward the window
to be wiped, whose surface to be wiped is suggested in FIG. 1 by a
dot-dash line 26. Since the dot-dash line 26 is meant to represent
the greatest curvature of the window surfaces, it is quite apparent
that the curvature of the wiper blade, which rests with its two
ends on the window, is greater than the maximum curvature of the
window. Under the contact pressure (arrow 24), the wiper blade
presses with its wiper lip 28 over its entire length against the
window surface 26. This causes a tension to build up in the
bandlike, spring-elastic support element 12, and this tension
assures a proper contact of the wiper strip 14 or wiper lip 28,
over their entire length, with the motor vehicle window.
It can be seen from FIG. 2 that the support element 12, seen there
in plan view, comprises a plurality of individual parts. For
instance, it has two spring rails 30 and 32, which in the exemplary
embodiment are joined together by clamplike or clawlike retaining
means 34 and 36 placed on both ends of the spring rails located
adjacent one another. As FIGS. 3 and 4 particularly show, each of
the two spring rails 30 and 32 is located in a respective
longitudinal groove 38 and 40 assigned to it in the wiper strip 14;
the grooves are disposed in the same plane and are thus opposite
one another. FIG. 2 also shows that both spring rails 30 and 32 are
wider in their middle region than in their end regions, because the
two outer longitudinal edges 42, 44, facing away from one another,
extend accordingly. The two inner longitudinal edges 46, 48 facing
toward one another are oriented parallel to one another, however.
These inner longitudinal edges 46 and 49 rest on the bottom of the
both respective longitudinal grooves 38 and 40. Since in the
exemplary embodiment the depth of the grooves is approximately
equal to the width of the spring rails 30 and 32 in their end
regions, toward the middle portion the two spring rails protrude
increasingly far out of the longitudinal grooves 38 and 40 with
their outer longitudinal edges 42 and 42 (see FIGS. 2, 3, and
4).
FIGS. 3 and 4 also show that the wiper strip 14 extends with a
constriction 50, dictated by the longitudinal grooves 38 and 40,
through the slot 52 (FIG. 2) that remains between the two inner
longitudinal edges 46 and 48, and after that the wiper strip widens
again on the side of the support element 12 facing away from the
window and is provided with a substantially triangular cross
section, which serves as a wind deflector strip. The one side face
56 of the wind deflector strip facing predominantly into the wind
(arrow 55 in FIG. 2) is scooped out in concave fashion. The second
side face 58 of the wind deflector strip is oriented essentially
perpendicular to the window 26, and the third side face 60 of the
wind deflector strip forms the wall, pointing away from the window,
of the two longitudinal grooves 38 and 40. As can be seen from the
dot-dash line in FIG. 2, the wiper strip 14 and the wind deflector
strip 54 integrated with it have a constant cross section, in this
exemplary embodiment. Nevertheless, it is also conceivable for at
least the cross section of the wind deflector strip 54 to be varied
over its length. The constant cross section over the length of the
wind deflector strip 54 in the exemplary embodiment does not,
however, preclude its being interrupted--as can be seen in FIG.
1--in the middle region of the wiper blade 10 by a recess 62, which
extends nearly to the support element 12. The connection device 16
for the wiper arm 18 is disposed in this recess 62. With pairs of
legs 64 and 66, the connection device 16 fits over and under the
spring rails 30 and 32 and keeps them in their prescribed position
in the longitudinal grooves 38 and 40. The legs 64 and 66 are
located on cheeks 68 and 70 of the connection device 16, which are
joined together by the pivot pins 22 already mentioned. The
connection device 16 thus forms a retaining means for the two
spring rails 30 and 32.
However, so that the spring rails 30 and 32 will remain with their
end regions properly within the longitudinal grooves 38 and 40,
further retaining means embodied as clamps 72 are provided, which
with claws 74 on their ends (see FIG. 5) reach around the spring
rails at their longitudinal edges 42 and 44 facing away from one
another. FIGS. 1 and 2 show that the spring rails 30 and 32 emerge
with their end portions from the longitudinal grooves 38 and 40,
because the wind deflector strip is slightly shorter than the
support element 12, and thus the clamps 74 can engage the end
portions of the support element. If the wiper blades are long
enough, then it may be expedient to dispose additional clawlike
retaining means along the length of the wiper blade; in that case,
a recess must then be assigned to them, to allow these clamps to
pass through the wind deflector strip 54.
It is clear from the above that besides the two spring rails 30 and
32, the support element 12 also includes retaining means, which
assure the securing of the support element to the wiper strip 14.
The connection device 16, however, is intended primarily to make a
pivotable connection possible between the wiper arm 18 and the
wiper blade 10. The connection device 16 furthermore has an
additional function, as already described, namely to secure the
spring rails 30 and 32 in their middle region.
In view of the various tasks to be taken on by the wiper lip 28 or
the wind deflector strip 54, the wiper strip can be made for
instance with the aid of what is known as multicomponent
extrusion.
Instead of the separate retaining means 34 and 36 at the ends of
the spring rails 30 and 32, it is also conceivable to embody these
retaining means as transverse legs, joined integrally to one or
both spring rails and extending to the other spring rail; their
free ends, bend into claws, then reach around this other spring
rail. Other forms of fastening, however, are also possible--such as
adhesive bonding, welding, and so forth.
* * * * *